Portable stand provided with latch mechanism for leg unit



p 22, 1959 E. J. PETRICK 2,905,420

PORTABLE STAND PROVIDED WITH LATCH MECHANISM FOR LEG UNIT Filed June 8, 1954 United States Patent PORTABLE STAND PROVIDED WITH LATCH NIECHANISM FOR LEG UNIT Edward J. Petrick, Park Ridge, Ill.

Application June 8,1954, Serial-No. 435,314 4 Claims. (Cl. 248-171) the leg members of a picture screen stand in folded.

position.

Another object is to provide a latch mechanism in which a lost motion connection permits relative movement between the leg unit and the standard to permit release of the leg unit from locked folded position.

A further object is to provide a'latch mechanism having spring means joining the leg unit and the bracing links to urge the leg unit upwardly when in folded position to retain the latch members in engagement.

Still another object is to provide a latch mechanism which is simple to assemble and inexpensive to manufacture, and which has yielding spring means on the leg unit to hold the latch members in engagement. Movie screen stands now in use generally have spring means supported within the main tubular standard. Such an arrangement is more difiicult to assemble and more costly to manufacture.

The invention is illustrated in the preferred embodiment in the accompanying drawings, in which:

Fig. 1 is a perspective View of the leg unit of a picture screen stand in outwardly spread supporting position;

Fig. 2, a broken fragmentary elevational view, partly in section showing a leg member in locked folded position;

Fig. 3, a view as in Fig. 2 showing a leg member in outwardly spread supporting position;

Fig. 4, a fragmentary sectional view taken as indicated on line 44 of Fig. 3; and

Fig. 5, a fragmentary sectional view taken as indicated on line 55 of Fig. 3.

In the embodiment illustrated, a standard 10, generally tubular and of metallic construction, is supported in upright position by a leg unit comprising a collar 11 slidable longitudinally of the standard, and a plurality of channel-shaped leg members 12 which are hinged to the collar 11 for movement from folded position adjacent the standard 10 to an outwardly spread supporting position, as shown in Fig. 1. Decorative plastic tips 12a may be provided on the free end of each leg member 12 to cover any sharp exposed metal edges. Although a cap 10a is shown in the drawings enclosing the lower end of the standard 10, such a cap is only decorative and is not needed because there is no spring means within the tubular standard 10 in the present invention.

A bracing link 13 preferably joins each leg member 12 to a fixture 14 embracing the lower end of the standard 10, and secured in place by a machine screw 15. The fixture, which is generally a metal stamping, has a plurality of stationary hook portions 16, preferably opening downwardly of the standard 10. Each of the hook Fee portions is adapted to receive-acooperating latching portio'nyherein shown asalatching'pin 17, on the lower portion of eachleg member 12 to fasten or-latch the leg unit in locked folded position.

'A plurality of tension springs 18 are provided to normally urgethe leg unit upwardly when in folded position to' maintain the latching pin 17 and the 'hook member 16 in'locking engagement. Each-spring is attached atone endjtoa crimped portion 19 in each leg member-12, and at the'other end to a rivet or connecting 'element 20 which pivotally joins each bracing link 13 to its respective leg member 12. It is preferred tohave a spring on each leg member, but itis clear that a single spring onone leg member will suflice.

A lost motion connection :is provided between the leg -members 12 and each bracing link 13 to permit latching and unlatching of the leg unit. As herein shown, it comprises an elongated slot 21 in each leg member 12 in which the rivet 20may slide when the leg unit is in folded position. Thetension in the spring 18 normally holds each rivet 20 inthe lower-end of each slot 21. To unlock the legunit from folded position, it is merely necessary to exert a downward pressure on the finger portion 22 which moves the leg unit downwardly with respect to the'bracinglinks 13 and permits each latching pin 17 to be removed from engagement with its respective hook portion 16. It is, of course, contemplated by the invention that the slot 21 be in the bracing link 13 rather than the leg member .12, in which event, the spring 18 need be arranged to normally maintain the rivet 20 in the upper end of the slot 21.

A torsion spring 23 having spring arms 24 and 25 may be provided encircling a rivet 26 which joins the collar 11 and the leg members 12. The spring 23 is torsioned so that it normally urges the leg members outwardly of the standard. Thus, when the latching pin is removed from engagement with the hook portion, the spring 23 immediately forces the leg members outwardly toward supporting position which in turn pivots each bracing link 13 outwardly and permits the collar 11 to slide downwardly of the standard 10.

To lock the legs in folded position, the collar is raised upwardly on the standard, and the lost motion connection between the leg members and bracing links permits the latching pin 17 to ride around the outer end 27 of the fixture 14 so that the pin 17 will nest within the hook portion 16, engagement being maintained by the tension slaring 18 urging the leg unit upwardly of the standard The foregoing detailed description is given for clearness of understanding only and no unnecessary limitations should be understood therefrom, for some modifications will be obvious to those skilled in the art.

I claim:

1. A portable stand, comprising: an upright standard; a collar slidable longitudinally of the standard; a plurality of leg members each hinged to the collar for movement from an outwardly spread supporting position to a folded position adjacent the standard, the free end portions of each of the leg members having a latching pin extending transversely thereof; a fixture secured to the lower end of the standard, said fixture mounting a plurality of downwardly turned hook portions each adapted to receive a latching pin to lock the leg members in folded position; bracing links joining each leg member to the fixture, each link and leg member being joined by a lost motion connection comprising a rivet slidably disposed in an elongated slot in each leg member; and tension springs on each leg member, each spring attached at one end to a respective l-eg member and at the other end to a respective rivet normally to retain the rivet at one end of its slot, said springs normally urging the leg members upwardly .when in folded position so that each of said latching pins is maintained in locking engagement within its respective hook portion, said leg members being movable downwardly in relation 'tothe bracing links torelease the latching pins and hook portions from locking engage ment so that the leg members may be swung to supporting position.

2. A portable stand, compnising: an upright standard; a leg unit having a plurality vof leg members and corresponding link members, an end of each link member being pivotally connected to its corresponding leg member, each of the pivotal connections including a slot in one of the members and a connecting element passing loosely through the slot and the other of the members to provide a lost motion connection and secure the members together in pivotal relation so that the leg members can move relative to the link members when folded to a position adjacent the standard; a first group of hinge connections joining an end of each leg member to the standard, and a second group of hinge connections joining the other end of each of the link members to the standard, one of said groups of binge connections being slidable longitudinally of the standard so that the leg members can be swung between an outwardly extended supporting position and a folded position adjacent the standard; a tension spring secured at one end to one of said connecting elements and being secured at the other end to said one member adjacent said one connecting element so that each of said connecting elements is yieldingly retained at one end of its slot when the leg members are in folded position; and a pair of cooperating latch members acting between the standard and leg unit for retaining the leg members in folded position, one of said latch members being secured to the leg unit and the other being secured to the standard, whereby relative yielding movement between said leg members and link members in folded position will move said one latch member relative to the other so that said latch members can be placed in latching engagement.

3. A pontable stand as specified in claim 2, in which the members having the slots are the leg members, and a tension spring is provided for each leg member, each of said tension springs being secured at one end to a connecting element and at the other end to the adjacent leg member.

4. A portable stand as specified in claim 3, in which the one latch member is a latching pin on a leg member of the leg unit and the other latch member is a hook portion secured to the standard in position to receive the latching pin when the leg members are moved to folded position.

References Cited in the file of this patent UNITED STATES PATENTS 904,319 Duncan Nov. 17, 1908 2,378,150 Michaud June 12, 1945 2,549,584 Eller Apr. 17, 1951 2,591,244 Du Mais et al. Apr. 1, 1952 2,708,559 Du Mais May 17, 1955 FOREIGN PATENTS 127,545 Austria Mar. 25, 1932 135,848 Austria Dec. 11, 1933 626,748 Germany Mar. 2, 1936 641,777 Germany Feb. 12, 1937 

